Association of Fetal Middle Cerebral Artery Doppler Indices in Different Positions and Adverse Perinatal Outcomes [40T]

Abstract

INTRODUCTION: Evidence has shown that “brain sparing” phenomenon can be replicated using maternal position as a physiological stress. Our study's objective is to ascertain if changes in Middle Cerebral Artery (MCA) Doppler pulsatility indices (PI) due to physiological stress caused by maternal position correlates with adverse perinatal outcomes in low risk and in high risk patients. METHODS: A prospective cohort study of singleton, nonanomalous pregnancies with chronic hypertension or pregestational diabetes, and low risk pregnancies between 18 and 36 weeks gestation. Pregnancies with Rh isoimmunizations, fetal growth restriction, maternal cardiac disease, smoking or drug use history were excluded. Fetal doppler velocimetry indices were obtained from the fetal MCA in maternal supine and left lateral decubitus position. ANOVA was used to compare demographics between cohorts and composite of adverse perinatal outcomes, which included fetal growth restriction, oligohydramnios and preeclampsia. RESULTS: The delta of MCA Doppler PI between the two maternal positions did not correlate with adverse perinatal outcome (p= 0.409). 89 patients were included. There were 34 (38.2%) women with adverse outcomes; 22 (64.7%) patients were from the low risk group and 12 (35.3%) patients were from the high risk group. CONCLUSION: Our preliminary study did not demonstrate correlation between delta fetal MCA Doppler indices and composite outcome. The limitation of this study was that it was not powered for the finding of high composite adverse outcome in the “low risk” group, which might suggest underlying unknown risks. More data is needed in order to address the significance of fetal MCA Doppler indices changes.